One more thing... You should be able to fit 275/60-15 DRs under the fish fenders on an 8" wheel. I have the SBP 8 3/4 in my fish using Wheel Vintique rallys and the combo looks fantastic IMO. Fronts are 14" on drums, so far. Great stance. Those wheels are heavy BTW.
BTW, crackedback has a MP 508 and that Comp 292H is about the same cam, I think. To each their own I suppose cause I loved the idle, power (cam came on at 2500 with a single plane intake which was where the vert started working solid), and sound. My car at 3050# and a 2500 converter and 3.91 gears went 7.20 at 98.